(1) Field of the Invention
This invention relates to a novel sialic acid derivative, more specifically to a sialic acid derivative having an active carbonyl group in the molecule, a biological half-life elongating agent for a physiologically active substance using said novel sialic acid derivative, a binder of coupling gel for affinity chromatography and a sialic acid derivative composed of said novel sialic acid derivative combined with various amino compounds such as an amino acid and a protein.
(2) Related Art Statement
It has been known that a neuraminic derivative such as an N-acetylnueraminic acid, i.e., a sialic acid derivative has been present in the animal kingdom or on a cell surface of some bacteria as a sialo-complex (glycoprotein, glycolipid, oligosaccharide and polysaccharaide).
In recent years, the above sialic acid derivative is a compound regarded inportant in medical and pharmaceutical fields such as nervous function, cancer, inflamation, immunity, virus infection, differentiation and hormone receptor, and has attracted attention as a pecular active molecule located on a cell surface.
However, the actual function of the sialic acid derivative in the aforesaid sialic acid complex, still remains a matter of conjucture.
Also, the sialic acid derivative has been researched by many natural organic chemists and various derivatives having simple structure have already been synthesized, but there has been not found a derivative which shows remarkable physiological activity.